ILLUSTRATIONS. XI 



A PLAN FOR PROMOTING THE WHITEFISH PRODUCTION OF THE GREAT LAKES: Page. 



Fig. I. Map of Lake Superior, showing whitefish area ^5^ 



2. Map of Lake Michigan, showing whitefish area °57 



3. Map of Lake Huron, showing whitefish area ^5° 



4. Map of Lake Erie, showing whitefish area ^59 



5. Map of Lake Ontario, showing whitefish area 660 



TEXT FIGURES— PART 2. 



FlSH-CULTURAL PRACTICES IN THE BUREAU OF FISHERIES: 



Fig. I. Clark-Williamson trough 7" 



2. Plan of barricade in Phinney Creek, near Birdsview, Washington 73° 



3. Front elevation of barricade shown in figure 2 73° 



4. Side elevation of barricade shown in figures 2 and 3 73i 



5. Section on line A-A of figure 2 73^ 



6. Detail showing method of fastening racks 73i 



7. Atkins-Dinsmore shipping case, longitudinal section 744 



8. Same, plan 744 



9. Same, cross section 745 



10. Argentine shipping case, section 74 



1 1 . Same, plan 749 



12. German-Chile shipping case, longitudinal section 75' 



13. Same, plan 75 



A NEW PRINCIPLE OF AQUICULTURE; 



Diagram of houseboat and floats [hatching and rearing apparatus] 766 



A METHOD OF CULTIVATING RAINBOW TROUT: 



Diagram i . Plan of ponds and spawning race 7^5 



2. Spawning race, sectional views 786 



3. Suggested arrangement of stream 786 



Apparatus and methods at marine hatchery, Flodevig, Norway: 



Fig. I . Plan of Flodevig hatching station ^°- 



2. Spawning pond, plan 3 



3. Same as figure 2, showing sections °°3 



4. Device for installation of egg collector 8°5 



5. Same as figure 4, showing section 8°5 



6. Hatching apparatus ° 



7. Incubator ' 



8. Mode of fastening incubator °°7 



Propagation and protection of the Rhine salmon: 



Fig. I. Diagram illustrating sizes of salmon ascending the Rhine 822 



2. Diagram showing ascent of Rhine salmon in different months 823 



Cultivation of the turbot: 



Fig. I. Early development of the turbot °°4 



2. Apparatus for hatching turbot *^7 



Treatment of fish-cultural waters for removal of alg^: 



Figs. I and 2. Apparatus for regulating flow of copper solution 877 



A device for counting young fish: 



Measure by means of which to count young fish i°03 



A method of measuring fish eggs. 



Fig I Metal trough for use in determining diameter of eggs 'O' ' 



2. Portion of diagram showing method of finding number of eggs per liquid quart. . . . 1014 

 An improvement in hatching and rearing boxes: 



Pig i_3. Design of proposed hatching and rearing box 



102 1 



